/* ===========================
   RESET & BASE STYLES
   =========================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Colors */
    --bg-primary: #0F172A;
    --bg-surface: #1E293B;
    --color-primary: #8B5CF6;
    --color-secondary: #06B6D4;
    --color-accent: #F43F5E;
    --color-success: #10B981;
    --color-warning: #F59E0B;
    --color-danger: #EF4444;
    --text-primary: #F8FAFC;
    --text-muted: #94A3B8;

    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #8B5CF6 0%, #6D28D9 100%);
    --gradient-secondary: linear-gradient(135deg, #06B6D4 0%, #0891B2 100%);
    --gradient-accent: linear-gradient(135deg, #F43F5E 0%, #E11D48 100%);

    /* Spacing */
    --spacing-xs: 8px;
    --spacing-sm: 12px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;

    /* Border Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;

    /* Shadows */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.2);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.3);

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --transition-slow: 350ms ease;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ===========================
   APP LAYOUT
   =========================== */
#app {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    max-width: 100%;
    margin: 0 auto;
    position: relative;
}

.app-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    z-index: 100;
    padding: var(--spacing-md) var(--spacing-lg);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.logo-icon {
    width: 40px;
    height: 40px;
    background: var(--gradient-primary);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 800;
    font-size: 18px;
    color: white;
    box-shadow: 0 4px 12px rgba(139, 92, 246, 0.4);
}

.logo-text {
    font-size: 20px;
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.icon-btn {
    background: var(--bg-surface);
    border: none;
    width: 44px;
    height: 44px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
    cursor: pointer;
    transition: all var(--transition-normal);
}

.icon-btn:hover {
    background: rgba(139, 92, 246, 0.1);
    color: var(--color-primary);
    transform: scale(1.05);
}

.app-main {
    flex: 1;
    padding: 80px var(--spacing-lg) 100px;
    max-width: 1200px;
    width: 100%;
    margin: 0 auto;
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ===========================
   BOTTOM NAVIGATION
   =========================== */
.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: rgba(30, 41, 59, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    display: flex;
    justify-content: space-around;
    padding: var(--spacing-sm) var(--spacing-md);
    z-index: 100;
}

.nav-item {
    background: none;
    border: none;
    color: var(--text-muted);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    padding: var(--spacing-xs);
    cursor: pointer;
    transition: all var(--transition-normal);
    flex: 1;
    max-width: 80px;
}

.nav-item span {
    font-size: 11px;
    font-weight: 500;
}

.nav-item.active {
    color: var(--color-primary);
}

.nav-item:hover {
    color: var(--color-primary);
    transform: translateY(-2px);
}

.nav-item svg {
    transition: all var(--transition-normal);
}

.nav-item.active svg {
    filter: drop-shadow(0 0 8px rgba(139, 92, 246, 0.6));
}

/* ===========================
   COMMON COMPONENTS
   =========================== */
.greeting {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
}

.subtitle {
    font-size: 16px;
    color: var(--text-muted);
    margin-bottom: var(--spacing-xl);
}

.section-title {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
}

.card {
    background: var(--bg-surface);
    border-radius: var(--radius-xl);
    padding: var(--spacing-lg);
    transition: all var(--transition-normal);
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.gradient-card {
    background: var(--gradient-primary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-lg);
    color: white;
    cursor: pointer;
    transition: all var(--transition-normal);
    box-shadow: 0 8px 24px rgba(139, 92, 246, 0.3);
}

.gradient-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 32px rgba(139, 92, 246, 0.5);
}

.btn-primary {
    background: var(--gradient-primary);
    border: none;
    color: white;
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 16px;
    cursor: pointer;
    transition: all var(--transition-normal);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    box-shadow: 0 4px 12px rgba(139, 92, 246, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(139, 92, 246, 0.5);
}

.btn-primary:active {
    transform: translateY(0);
}

/* ===========================
   STATS ROW
   =========================== */
.stats-row {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
}

.stat-card {
    background: var(--bg-surface);
    padding: var(--spacing-md);
    border-radius: var(--radius-lg);
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.stat-card:hover {
    transform: translateY(-4px);
    background: rgba(139, 92, 246, 0.1);
}

.stat-card svg {
    margin-bottom: var(--spacing-sm);
}

.stat-value {
    font-size: 18px;
    font-weight: 700;
    margin: var(--spacing-sm) 0 4px;
}

.stat-label {
    font-size: 12px;
    color: var(--text-muted);
}

/* ===========================
   TASK ITEMS
   =========================== */
.task-item {
    background: var(--bg-surface);
    padding: var(--spacing-md);
    border-radius: var(--radius-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-sm);
    cursor: pointer;
    transition: all var(--transition-normal);
}

.task-item:hover {
    background: rgba(139, 92, 246, 0.1);
    transform: translateX(4px);
}

.task-info {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.task-status {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--color-primary);
}

.task-status.completed {
    background: var(--color-success);
}

.task-title {
    font-weight: 600;
    font-size: 16px;
}

.task-time {
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 4px;
}

/* ===========================
   EXERCISE CARDS
   =========================== */
.exercise-card {
    background: var(--bg-surface);
    padding: var(--spacing-md);
    border-radius: var(--radius-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-sm);
    transition: all var(--transition-normal);
}

.exercise-card:hover {
    background: rgba(139, 92, 246, 0.1);
    transform: translateX(4px);
}

.ex-name {
    font-weight: 600;
    font-size: 16px;
}

.ex-details {
    font-size: 14px;
    color: var(--text-muted);
    margin-top: 4px;
}

.ex-badge {
    background: rgba(139, 92, 246, 0.1);
    padding: 6px 12px;
    border-radius: var(--radius-sm);
    font-size: 12px;
    font-weight: 700;
    color: var(--color-primary);
}

/* ===========================
   RECIPE CARDS
   =========================== */
.recipe-card {
    background: var(--bg-surface);
    padding: var(--spacing-sm);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
    cursor: pointer;
    transition: all var(--transition-normal);
}

.recipe-card:hover {
    background: rgba(139, 92, 246, 0.1);
    transform: translateX(4px);
}

.recipe-img {
    width: 70px;
    height: 70px;
    border-radius: var(--radius-md);
    object-fit: cover;
}

.recipe-info {
    flex: 1;
}

.recipe-type {
    font-size: 12px;
    font-weight: 700;
    color: var(--color-primary);
    text-transform: uppercase;
}

.recipe-title {
    font-weight: 600;
    font-size: 16px;
    margin-top: 4px;
}

.recipe-meta {
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 4px;
}

/* ===========================
   FEATURED WORKOUT
   =========================== */
.featured-card {
    position: relative;
    height: 200px;
    border-radius: var(--radius-xl);
    overflow: hidden;
    margin-bottom: var(--spacing-xl);
    cursor: pointer;
}

.featured-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.featured-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(to top, rgba(0, 0, 0, 0.8), transparent);
}

.featured-label {
    position: absolute;
    bottom: var(--spacing-lg);
    left: var(--spacing-lg);
    color: white;
}

.featured-title {
    font-size: 20px;
    font-weight: 700;
}

.featured-subtitle {
    font-size: 14px;
    opacity: 0.8;
    margin-top: 4px;
}

.play-button {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: var(--color-primary);
    border: none;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-normal);
    box-shadow: 0 8px 24px rgba(139, 92, 246, 0.5);
}

.play-button:hover {
    transform: translate(-50%, -50%) scale(1.1);
    box-shadow: 0 12px 32px rgba(139, 92, 246, 0.7);
}

/* ===========================
   TABS
   =========================== */
.tabs {
    display: flex;
    background: var(--bg-surface);
    border-radius: var(--radius-md);
    padding: 4px;
    margin-bottom: var(--spacing-lg);
}

.tab {
    flex: 1;
    padding: var(--spacing-sm);
    background: none;
    border: none;
    color: var(--text-muted);
    font-weight: 600;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-normal);
}

.tab.active {
    background: var(--color-primary);
    color: white;
}

/* ===========================
   TIP BOX
   =========================== */
.tip-box {
    background: rgba(245, 158, 11, 0.1);
    padding: var(--spacing-lg);
    border-radius: var(--radius-xl);
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    margin: var(--spacing-xl) 0;
}

.tip-title {
    font-weight: 700;
    font-size: 16px;
    color: var(--color-warning);
}

.tip-text {
    font-size: 14px;
    color: var(--text-primary);
    margin-top: 4px;
}

/* ===========================
   AI CARD
   =========================== */
.ai-card {
    background: var(--gradient-secondary);
    padding: var(--spacing-lg);
    border-radius: var(--radius-xl);
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-xl);
    cursor: pointer;
    transition: all var(--transition-normal);
    box-shadow: 0 8px 24px rgba(6, 182, 212, 0.3);
}

.ai-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 32px rgba(6, 182, 212, 0.5);
}

.ai-info {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    color: white;
}

.ai-title {
    font-size: 18px;
    font-weight: 700;
}

.ai-subtitle {
    font-size: 12px;
    opacity: 0.9;
    margin-top: 4px;
}

/* ===========================
   TIMER DISPLAY
   =========================== */
.timer-display {
    text-align: center;
    margin: var(--spacing-xl) 0;
}

.timer-value {
    font-size: 72px;
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1;
}

.timer-label {
    font-size: 16px;
    color: var(--text-muted);
    margin-top: var(--spacing-sm);
}

/* ===========================
   ACHIEVEMENT BADGE
   =========================== */
.achievement-badge {
    background: var(--bg-surface);
    padding: var(--spacing-lg);
    border-radius: var(--radius-xl);
    text-align: center;
    transition: all var(--transition-normal);
}

.achievement-badge:hover {
    transform: translateY(-4px);
    background: rgba(139, 92, 246, 0.1);
}

.achievement-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto var(--spacing-md);
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 40px;
    box-shadow: 0 8px 24px rgba(139, 92, 246, 0.4);
}

.achievement-name {
    font-weight: 700;
    font-size: 16px;
    margin-bottom: 4px;
}

.achievement-desc {
    font-size: 12px;
    color: var(--text-muted);
}

/* ===========================
   PROGRESS BAR
   =========================== */
.progress-container {
    margin: var(--spacing-lg) 0;
}

.progress-bar {
    height: 12px;
    background: var(--bg-surface);
    border-radius: 999px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--gradient-primary);
    border-radius: 999px;
    transition: width var(--transition-slow);
}

.progress-text {
    display: flex;
    justify-content: space-between;
    margin-top: var(--spacing-sm);
    font-size: 14px;
    color: var(--text-muted);
}

/* ===========================
   RESPONSIVE DESIGN
   =========================== */
@media (min-width: 768px) {
    .app-main {
        padding: 100px var(--spacing-xl) 120px;
    }

    .bottom-nav {
        max-width: 600px;
        left: 50%;
        transform: translateX(-50%);
        border-radius: var(--radius-xl) var(--radius-xl) 0 0;
    }

    .stats-row {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* ===========================
   UTILITIES
   =========================== */
.hidden {
    display: none !important;
}

.text-center {
    text-align: center;
}

.mb-sm {
    margin-bottom: var(--spacing-sm);
}

.mb-md {
    margin-bottom: var(--spacing-md);
}

.mb-lg {
    margin-bottom: var(--spacing-lg);
}

.mb-xl {
    margin-bottom: var(--spacing-xl);
}

.mt-sm {
    margin-top: var(--spacing-sm);
}

.mt-md {
    margin-top: var(--spacing-md);
}

.mt-lg {
    margin-top: var(--spacing-lg);
}

.mt-xl {
    margin-top: var(--spacing-xl);
}