/* ==========================================================================
   AI STUDY BUDDY - PREMIUM GLASSMORPHISM DARK DESIGN SYSTEM
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Fira+Code:wght@400;500;600&family=Outfit:wght@300;400;500;600;700;800&display=swap');

:root {
    /* Color Palette */
    --bg-dark: #0B0F19;
    --bg-card: rgba(23, 31, 51, 0.65);
    --bg-card-hover: rgba(30, 41, 67, 0.85);
    --bg-panel: rgba(15, 23, 42, 0.75);
    --bg-input: rgba(10, 16, 30, 0.8);
    
    --primary: #8B5CF6;
    --primary-light: #A78BFA;
    --primary-dark: #6D28D9;
    --primary-glow: rgba(139, 92, 246, 0.35);

    --secondary: #06B6D4;
    --secondary-glow: rgba(6, 182, 212, 0.35);

    --accent-emerald: #10B981;
    --accent-amber: #F59E0B;
    --accent-rose: #F43F5E;

    --text-main: #F8FAFC;
    --text-muted: #94A3B8;
    --text-dim: #64748B;

    --border-color: rgba(255, 255, 255, 0.1);
    --border-glow: rgba(139, 92, 246, 0.5);

    --glass-blur: blur(16px);
    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 20px;
    --radius-full: 9999px;

    --shadow-subtle: 0 10px 30px -10px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 25px rgba(139, 92, 246, 0.25);

    --font-ui: 'Outfit', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-code: 'Fira Code', monospace;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-ui);
    background-color: var(--bg-dark);
    background-image: 
        radial-gradient(circle at 15% 15%, rgba(139, 92, 246, 0.15) 0%, transparent 40%),
        radial-gradient(circle at 85% 85%, rgba(6, 182, 212, 0.12) 0%, transparent 40%);
    color: var(--text-main);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}
::-webkit-scrollbar-track {
    background: rgba(11, 15, 25, 0.5);
}
::-webkit-scrollbar-thumb {
    background: rgba(148, 163, 184, 0.25);
    border-radius: var(--radius-full);
}
::-webkit-scrollbar-thumb:hover {
    background: var(--primary);
}

/* ==========================================================================
   HEADER & TOP NAVBAR
   ========================================================================== */

.app-header {
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: var(--glass-blur);
    border-bottom: 1px solid var(--border-color);
    padding: 0.85rem 2rem;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-container {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1.5rem;
}

.logo-wrapper {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.logo-icon {
    font-size: 1.8rem;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    filter: drop-shadow(0 0 10px var(--primary-glow));
}

.logo-title {
    font-size: 1.4rem;
    font-weight: 800;
    letter-spacing: -0.5px;
    background: linear-gradient(135deg, #FFF, #94A3B8);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.badge-tag {
    font-size: 0.75rem;
    font-weight: 600;
    padding: 0.2rem 0.6rem;
    border-radius: var(--radius-full);
    background: rgba(139, 92, 246, 0.15);
    color: var(--primary-light);
    border: 1px solid rgba(139, 92, 246, 0.3);
    margin-left: 0.4rem;
}

.header-controls {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.subject-picker {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 0.4rem 0.8rem;
}

.subject-select {
    background: transparent;
    border: none;
    color: var(--text-main);
    font-family: var(--font-ui);
    font-size: 0.9rem;
    font-weight: 500;
    outline: none;
    cursor: pointer;
}

.subject-select option {
    background: var(--bg-dark);
    color: var(--text-main);
}

.api-status-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 0.45rem 0.9rem;
    color: var(--text-muted);
    font-size: 0.85rem;
    cursor: pointer;
    transition: all 0.2s ease;
}

.api-status-btn:hover {
    border-color: var(--primary-light);
    color: var(--text-main);
    box-shadow: 0 0 15px var(--primary-glow);
}

.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--text-dim);
}
.status-dot.online {
    background: var(--accent-emerald);
    box-shadow: 0 0 8px var(--accent-emerald);
}
.status-dot.warning {
    background: var(--accent-amber);
    box-shadow: 0 0 8px var(--accent-amber);
}

/* ==========================================================================
   NAVIGATION TAB BAR
   ========================================================================== */

.nav-bar {
    background: rgba(11, 15, 25, 0.6);
    backdrop-filter: var(--glass-blur);
    border-bottom: 1px solid var(--border-color);
    padding: 0.5rem 2rem;
}

.nav-container {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    gap: 0.75rem;
    overflow-x: auto;
}

.nav-tab {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    padding: 0.6rem 1.2rem;
    background: transparent;
    border: none;
    border-radius: var(--radius-md);
    color: var(--text-muted);
    font-family: var(--font-ui);
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.25 ease;
    white-space: nowrap;
}

.nav-tab:hover {
    color: var(--text-main);
    background: rgba(255, 255, 255, 0.05);
}

.nav-tab.active {
    color: #FFF;
    background: linear-gradient(135deg, rgba(139, 92, 246, 0.25), rgba(6, 182, 212, 0.15));
    border: 1px solid rgba(139, 92, 246, 0.4);
    box-shadow: 0 0 15px var(--primary-glow);
}

/* ==========================================================================
   MAIN APP LAYOUT
   ========================================================================== */

.app-main {
    max-width: 1400px;
    margin: 0 auto;
    padding: 1.5rem 2rem;
    flex: 1;
    width: 100%;
    display: flex;
    flex-direction: column;
}

.tab-panel {
    display: none;
    flex: 1;
    animation: fadeIn 0.3s ease;
}

.tab-panel.active {
    display: flex;
    flex-direction: column;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(6px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ==========================================================================
   TAB 1: AI TUTOR CHAT HUB
   ========================================================================== */

.chat-panel-container {
    display: flex;
    flex-direction: column;
    height: calc(100vh - 180px);
    background: var(--bg-card);
    backdrop-filter: var(--glass-blur);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-subtle);
}

.chat-header-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 1.5rem;
    background: rgba(15, 23, 42, 0.5);
    border-bottom: 1px solid var(--border-color);
    flex-wrap: wrap;
    gap: 1rem;
}

.persona-group {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.persona-btn {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.4rem 0.8rem;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-full);
    color: var(--text-muted);
    font-size: 0.85rem;
    cursor: pointer;
    transition: all 0.2s ease;
}

.persona-btn:hover {
    color: var(--text-main);
    background: rgba(255, 255, 255, 0.08);
}

.persona-btn.active {
    background: var(--primary);
    color: #FFF;
    border-color: var(--primary-light);
    box-shadow: 0 0 12px var(--primary-glow);
}

.chat-actions {
    display: flex;
    gap: 0.5rem;
}

.chat-messages {
    flex: 1;
    padding: 1.5rem;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 1.2rem;
}

/* Chat Welcome Screen */
.chat-welcome {
    margin: auto;
    text-align: center;
    max-width: 580px;
    padding: 2rem;
}

.welcome-icon {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    animation: bounce 2s infinite ease-in-out;
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-8px); }
}

.chat-welcome h3 {
    font-size: 1.6rem;
    font-weight: 700;
    margin-bottom: 0.6rem;
}

.chat-welcome p {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.welcome-suggestions {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.suggestion-card {
    display: flex;
    align-items: center;
    gap: 1rem;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 0.8rem 1.2rem;
    color: var(--text-main);
    cursor: pointer;
    text-align: left;
    transition: all 0.2s ease;
}

.suggestion-card:hover {
    background: rgba(139, 92, 246, 0.12);
    border-color: var(--primary-light);
    transform: translateX(4px);
}

/* Chat Messages */
.chat-message {
    display: flex;
    gap: 1rem;
    max-width: 88%;
    animation: fadeIn 0.25s ease;
}

.chat-message.user-message {
    margin-left: auto;
    flex-direction: row-reverse;
}

.chat-message.ai-message {
    margin-right: auto;
}

.message-avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid var(--border-color);
    flex-shrink: 0;
}

.user-message .message-avatar {
    background: linear-gradient(135deg, var(--secondary), #0284C7);
}

.ai-message .message-avatar {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    box-shadow: 0 0 10px var(--primary-glow);
}

.message-content {
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
}

.message-header {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    font-size: 0.78rem;
    color: var(--text-dim);
}

.user-message .message-header {
    justify-content: flex-end;
}

.message-body {
    background: rgba(30, 41, 59, 0.7);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1rem 1.2rem;
    line-height: 1.65;
    font-size: 0.95rem;
}

.user-message .message-body {
    background: linear-gradient(135deg, rgba(139, 92, 246, 0.2), rgba(6, 182, 212, 0.15));
    border-color: rgba(139, 92, 246, 0.4);
    border-top-right-radius: 2px;
}

.ai-message .message-body {
    border-top-left-radius: 2px;
}

.speech-btn {
    background: transparent;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    font-size: 0.75rem;
    display: flex;
    align-items: center;
    gap: 0.2rem;
}
.speech-btn:hover { color: var(--primary-light); }

/* Typing indicator */
.typing-indicator {
    display: flex;
    gap: 0.4rem;
    padding: 0.5rem 0.2rem;
}

.typing-indicator span {
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: var(--primary-light);
    animation: typing 1.4s infinite ease-in-out;
}

.typing-indicator span:nth-child(2) { animation-delay: 0.2s; }
.typing-indicator span:nth-child(3) { animation-delay: 0.4s; }

@keyframes typing {
    0%, 100% { opacity: 0.3; transform: scale(0.8); }
    50% { opacity: 1; transform: scale(1.2); }
}

/* Chat Input Bar */
.chat-input-bar {
    padding: 1rem 1.5rem;
    background: rgba(15, 23, 42, 0.8);
    border-top: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.quick-prompts-row {
    display: flex;
    gap: 0.5rem;
    overflow-x: auto;
    padding-bottom: 0.2rem;
}

.quick-prompt-chip {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-full);
    padding: 0.3rem 0.75rem;
    color: var(--text-muted);
    font-size: 0.78rem;
    white-space: nowrap;
    cursor: pointer;
    transition: all 0.2s ease;
}

.quick-prompt-chip:hover {
    color: var(--text-main);
    border-color: var(--primary-light);
    background: rgba(139, 92, 246, 0.1);
}

.input-wrapper {
    display: flex;
    align-items: flex-end;
    gap: 0.75rem;
    background: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 0.5rem 0.75rem;
    transition: border-color 0.2s ease;
}

.input-wrapper:focus-within {
    border-color: var(--primary);
    box-shadow: 0 0 15px var(--primary-glow);
}

.chat-textarea {
    flex: 1;
    background: transparent;
    border: none;
    color: var(--text-main);
    font-family: var(--font-ui);
    font-size: 0.95rem;
    outline: none;
    resize: none;
    max-height: 180px;
    line-height: 1.5;
}

.voice-btn, .send-btn {
    background: transparent;
    border: none;
    color: var(--text-muted);
    font-size: 1.2rem;
    cursor: pointer;
    padding: 0.4rem;
    border-radius: var(--radius-sm);
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.voice-btn:hover { color: var(--secondary); }
.voice-btn.listening {
    color: var(--accent-rose);
    animation: pulse 1s infinite alternate;
}

@keyframes pulse {
    from { transform: scale(1); }
    to { transform: scale(1.15); }
}

.send-btn {
    background: var(--primary);
    color: #FFF;
    padding: 0.5rem 0.8rem;
    border-radius: var(--radius-md);
}

.send-btn:hover {
    background: var(--primary-light);
    box-shadow: 0 0 12px var(--primary-glow);
}

/* Formatting Code Blocks */
.code-block-wrapper {
    background: #090D16;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    margin: 0.8rem 0;
    overflow: hidden;
}

.code-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.4rem 0.8rem;
    background: rgba(255, 255, 255, 0.04);
    border-bottom: 1px solid var(--border-color);
    font-size: 0.75rem;
    color: var(--text-muted);
}

.code-copy-btn {
    background: transparent;
    border: none;
    color: var(--primary-light);
    cursor: pointer;
    font-size: 0.75rem;
}

pre {
    padding: 1rem;
    overflow-x: auto;
    font-family: var(--font-code);
    font-size: 0.88rem;
    line-height: 1.5;
}

code {
    font-family: var(--font-code);
    background: rgba(255, 255, 255, 0.08);
    padding: 0.15rem 0.4rem;
    border-radius: 4px;
    font-size: 0.88em;
}

pre code {
    background: transparent;
    padding: 0;
}

blockquote {
    border-left: 3px solid var(--primary);
    padding-left: 0.8rem;
    color: var(--text-muted);
    margin: 0.5rem 0;
}

/* ==========================================================================
   TAB 2: FLASHCARD STUDIO
   ========================================================================== */

.flashcard-panel-container {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.deck-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
}

.deck-card {
    background: var(--bg-card);
    backdrop-filter: var(--glass-blur);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
    position: relative;
    overflow: hidden;
}

.deck-card:hover {
    border-color: var(--primary-light);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.new-deck-card {
    border-style: dashed;
    align-items: center;
    justify-content: center;
    text-align: center;
}

.new-deck-icon {
    font-size: 2.5rem;
    color: var(--primary-light);
}

.deck-badge {
    align-self: flex-start;
    font-size: 0.75rem;
    padding: 0.2rem 0.6rem;
    border-radius: var(--radius-full);
    background: rgba(6, 182, 212, 0.15);
    color: var(--secondary);
}

.deck-actions {
    display: flex;
    gap: 0.5rem;
    margin-top: auto;
    padding-top: 0.5rem;
}

/* 3D Flashcard Interface */
.flashcard-study-container {
    max-width: 650px;
    margin: 2rem auto;
    width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
}

.card-progress-bar-bg {
    width: 100%;
    height: 6px;
    background: rgba(255, 255, 255, 0.08);
    border-radius: var(--radius-full);
    overflow: hidden;
}

.card-progress-bar-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    width: 0%;
    transition: width 0.3s ease;
}

.flashcard-wrapper {
    perspective: 1000px;
    width: 100%;
    height: 340px;
    cursor: pointer;
}

.flashcard-inner {
    position: relative;
    width: 100%;
    height: 100%;
    text-align: center;
    transition: transform 0.6s cubic-bezier(0.4, 0.2, 0.2, 1);
    transform-style: preserve-3d;
}

.flashcard-inner.flipped {
    transform: rotateY(180deg);
}

.flashcard-front, .flashcard-back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    backdrop-filter: var(--glass-blur);
    padding: 2.5rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-subtle);
}

.flashcard-front {
    background: linear-gradient(145deg, rgba(23, 31, 51, 0.9), rgba(15, 23, 42, 0.9));
}

.flashcard-back {
    background: linear-gradient(145deg, rgba(30, 27, 75, 0.95), rgba(15, 23, 42, 0.95));
    border-color: var(--primary-light);
    transform: rotateY(180deg);
}

.card-label {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-dim);
    margin-bottom: 1rem;
}

.card-content {
    font-size: 1.3rem;
    font-weight: 500;
    line-height: 1.5;
}

.card-hint-text {
    margin-top: auto;
    font-size: 0.8rem;
    color: var(--text-muted);
}

.flashcard-controls {
    display: flex;
    gap: 1rem;
    align-items: center;
}

/* ==========================================================================
   TAB 3: INTERACTIVE QUIZ HUB
   ========================================================================== */

.quiz-panel-container {
    max-width: 800px;
    margin: 0 auto;
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.quiz-generator-box {
    background: var(--bg-card);
    backdrop-filter: var(--glass-blur);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    display: flex;
    gap: 1rem;
    align-items: center;
}

.quiz-topic-input {
    flex: 1;
    background: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 0.75rem 1rem;
    color: var(--text-main);
    font-family: var(--font-ui);
    font-size: 1rem;
    outline: none;
}

.quiz-card {
    background: var(--bg-card);
    backdrop-filter: var(--glass-blur);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 2rem;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.quiz-question {
    font-size: 1.25rem;
    font-weight: 600;
    line-height: 1.5;
}

.quiz-options {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.quiz-option {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem 1.2rem;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-main);
    font-family: var(--font-ui);
    font-size: 0.95rem;
    cursor: pointer;
    text-align: left;
    transition: all 0.2s ease;
}

.quiz-option:hover:not(:disabled) {
    background: rgba(139, 92, 246, 0.12);
    border-color: var(--primary-light);
}

.quiz-option.correct {
    background: rgba(16, 185, 129, 0.2);
    border-color: var(--accent-emerald);
    color: #FFF;
}

.quiz-option.wrong {
    background: rgba(244, 63, 94, 0.2);
    border-color: var(--accent-rose);
    color: #FFF;
}

.opt-prefix {
    width: 28px;
    height: 28px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 0.85rem;
}

.quiz-explanation {
    background: rgba(15, 23, 42, 0.8);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1rem 1.2rem;
    line-height: 1.5;
    font-size: 0.9rem;
}

.quiz-result-card {
    text-align: center;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 3rem 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.2rem;
}

.score-circle {
    width: 140px;
    height: 140px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-glow);
}

.score-num { font-size: 1.8rem; font-weight: 800; }
.score-pct { font-size: 0.9rem; opacity: 0.9; }

/* ==========================================================================
   TAB 4: POMODORO & FOCUS SOUND GENERATOR
   ========================================================================== */

.timer-panel-container {
    max-width: 600px;
    margin: 1rem auto;
    width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2rem;
}

.timer-modes {
    display: flex;
    gap: 0.5rem;
    background: var(--bg-card);
    padding: 0.4rem;
    border-radius: var(--radius-full);
    border: 1px solid var(--border-color);
}

.timer-mode-btn {
    padding: 0.5rem 1.2rem;
    background: transparent;
    border: none;
    border-radius: var(--radius-full);
    color: var(--text-muted);
    font-family: var(--font-ui);
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
}

.timer-mode-btn.active {
    background: var(--primary);
    color: #FFF;
}

.timer-display-wrapper {
    position: relative;
    width: 260px;
    height: 260px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.timer-svg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    transform: rotate(-90deg);
}

.timer-bg-ring {
    fill: none;
    stroke: rgba(255, 255, 255, 0.06);
    stroke-width: 8;
}

.timer-progress-ring {
    fill: none;
    stroke: var(--primary-light);
    stroke-width: 8;
    stroke-linecap: round;
    transition: stroke-dashoffset 0.3s linear;
    filter: drop-shadow(0 0 8px var(--primary-glow));
}

.timer-digits {
    font-size: 3.5rem;
    font-weight: 800;
    letter-spacing: -1px;
    z-index: 10;
}

.timer-sound-controls {
    background: var(--bg-card);
    backdrop-filter: var(--glass-blur);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 1.2rem 1.5rem;
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
}

.sound-select-box {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* ==========================================================================
   TAB 5: SMART NOTES MANAGER
   ========================================================================== */

.notes-panel-container {
    display: flex;
    gap: 1.5rem;
    height: calc(100vh - 180px);
}

.notes-sidebar {
    width: 280px;
    background: var(--bg-card);
    backdrop-filter: var(--glass-blur);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 1.2rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.notes-editor-main {
    flex: 1;
    background: var(--bg-card);
    backdrop-filter: var(--glass-blur);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.note-title-input {
    background: transparent;
    border: none;
    border-bottom: 1px solid var(--border-color);
    color: var(--text-main);
    font-family: var(--font-ui);
    font-size: 1.4rem;
    font-weight: 700;
    padding: 0.5rem 0;
    outline: none;
}

.note-ai-toolbar {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.note-textarea {
    flex: 1;
    background: rgba(10, 16, 30, 0.5);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1rem;
    color: var(--text-main);
    font-family: var(--font-ui);
    font-size: 1rem;
    line-height: 1.6;
    outline: none;
    resize: none;
}

.note-item {
    padding: 0.75rem;
    border-radius: var(--radius-md);
    border: 1px solid transparent;
    cursor: pointer;
    transition: all 0.2s ease;
}

.note-item:hover {
    background: rgba(255, 255, 255, 0.05);
}

.note-item.active {
    background: rgba(139, 92, 246, 0.15);
    border-color: var(--primary-light);
}

.note-title { font-weight: 600; font-size: 0.95rem; }
.note-date { font-size: 0.75rem; color: var(--text-dim); margin-top: 0.2rem; }

/* ==========================================================================
   BUTTONS & GENERAL UTILITIES
   ========================================================================== */

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: #FFF;
    border: none;
    border-radius: var(--radius-md);
    padding: 0.65rem 1.4rem;
    font-family: var(--font-ui);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    box-shadow: 0 0 15px var(--primary-glow);
}

.btn-primary:hover {
    filter: brightness(1.15);
    transform: translateY(-1px);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.08);
    color: var(--text-main);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 0.65rem 1.4rem;
    font-family: var(--font-ui);
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.15);
}

.btn-sm {
    padding: 0.35rem 0.7rem;
    font-size: 0.8rem;
}

.btn-danger {
    background: rgba(244, 63, 94, 0.15);
    color: var(--accent-rose);
    border: 1px solid rgba(244, 63, 94, 0.3);
    border-radius: var(--radius-md);
    cursor: pointer;
}
.btn-danger:hover { background: rgba(244, 63, 94, 0.3); }

/* ==========================================================================
   MODAL WINDOWS
   ========================================================================== */

.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(5, 8, 15, 0.8);
    backdrop-filter: blur(8px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease;
}

.modal-overlay.active {
    opacity: 1;
    pointer-events: auto;
}

.modal-box {
    background: var(--bg-card);
    border: 1px solid var(--border-glow);
    border-radius: var(--radius-lg);
    width: 90%;
    max-width: 520px;
    padding: 2rem;
    box-shadow: var(--shadow-subtle);
    display: flex;
    flex-direction: column;
    gap: 1.2rem;
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-close-btn {
    background: transparent;
    border: none;
    color: var(--text-muted);
    font-size: 1.4rem;
    cursor: pointer;
}

.api-key-input {
    width: 100%;
    background: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 0.75rem 1rem;
    color: var(--text-main);
    font-family: var(--font-code);
    font-size: 0.9rem;
    outline: none;
}

/* ==========================================================================
   TOAST NOTIFICATION SYSTEM
   ========================================================================== */

.toast-container {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    z-index: 2000;
}

.toast {
    background: rgba(15, 23, 42, 0.9);
    border: 1px solid var(--border-color);
    backdrop-filter: var(--glass-blur);
    padding: 0.8rem 1.2rem;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-subtle);
    animation: slideInRight 0.3s ease;
}

.toast-success { border-color: var(--accent-emerald); }
.toast-error { border-color: var(--accent-rose); }
.toast-warning { border-color: var(--accent-amber); }

.toast-content {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    font-size: 0.9rem;
}

@keyframes slideInRight {
    from { transform: translateX(100%); opacity: 0; }
    to { transform: translateX(0); opacity: 1; }
}

.toast.fade-out {
    opacity: 0;
    transform: translateY(10px);
    transition: all 0.3s ease;
}

/* Spinner */
.spinner {
    width: 36px;
    height: 36px;
    border: 3px solid rgba(255,255,255,0.1);
    border-top-color: var(--primary-light);
    border-radius: 50%;
    animation: spin 0.8s infinite linear;
}
@keyframes spin { to { transform: rotate(360deg); } }

.loading-spinner-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 3rem;
    gap: 1rem;
    color: var(--text-muted);
}