/* myPhysio - Main Styles */
:root {
    --color-primary: #2563eb;
    --color-primary-dark: #1d4ed8;
    --color-primary-light: #3b82f6;
    --color-primary-bg: #eff6ff;
    --color-secondary: #0d9488;
    --color-bg: #f8fafc;
    --color-surface: #ffffff;
    --color-border: #e2e8f0;
    --color-text: #1e293b;
    --color-text-secondary: #64748b;
    --color-text-muted: #94a3b8;
    --color-text-inverse: #ffffff;
    --color-success: #10b981;
    --color-error: #ef4444;
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-family-display: 'Plus Jakarta Sans', var(--font-family);
    --space-1: 0.25rem; --space-2: 0.5rem; --space-3: 0.75rem;
    --space-4: 1rem; --space-5: 1.25rem; --space-6: 1.5rem;
    --space-8: 2rem; --space-10: 2.5rem; --space-12: 3rem;
    --radius-sm: 0.375rem; --radius-md: 0.5rem; --radius-lg: 0.75rem;
    --radius-xl: 1rem; --radius-2xl: 1.5rem; --radius-full: 9999px;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --header-height: 60px;
    --nav-height: 64px;
    --content-padding: var(--space-4);
    --z-dropdown: 100; --z-sticky: 200; --z-modal-backdrop: 300;
    --z-modal: 400; --z-toast: 500;
}
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; }
body {
    font-family: var(--font-family);
    color: var(--color-text);
    background: var(--color-bg);
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
}
img, video { max-width: 100%; height: auto; display: block; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }
input, textarea, select { font-family: inherit; font-size: inherit; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
h1, h2, h3, h4 { font-family: var(--font-family-display); font-weight: 700; line-height: 1.25; }
.hidden { display: none !important; }

/* App Container */
.app-container { display: flex; flex-direction: column; min-height: 100vh; padding-bottom: var(--nav-height); }
.page { flex: 1; padding: var(--content-padding); padding-top: calc(var(--header-height) + var(--space-4)); }

/* Header */
.header {
    position: fixed; top: 0; left: 0; right: 0;
    height: var(--header-height);
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    z-index: var(--z-sticky);
    display: flex; align-items: center;
    padding: 0 var(--content-padding);
}
.header__logo {
    display: flex; align-items: center; gap: var(--space-2);
    font-family: var(--font-family-display);
    font-weight: 700; font-size: 1.25rem;
    color: var(--color-primary);
}
.header__logo-icon { width: 32px; height: 32px; }
.header__actions { margin-left: auto; display: flex; align-items: center; gap: var(--space-2); }

/* Bottom Nav */
.bottom-nav {
    position: fixed; bottom: 0; left: 0; right: 0;
    height: var(--nav-height);
    background: var(--color-surface);
    border-top: 1px solid var(--color-border);
    z-index: var(--z-sticky);
    display: flex; justify-content: space-around; align-items: center;
    padding: var(--space-2) 0;
    padding-bottom: max(var(--space-2), env(safe-area-inset-bottom));
}
.nav-item {
    display: flex; flex-direction: column; align-items: center;
    gap: var(--space-1); padding: var(--space-2);
    color: var(--color-text-muted);
    transition: color var(--transition-fast);
    position: relative; min-width: 64px;
}
.nav-item:active, .nav-item.active { color: var(--color-primary); }
.nav-item__icon { width: 24px; height: 24px; }
.nav-item__label { font-size: 0.75rem; font-weight: 500; }
.nav-item__badge {
    position: absolute; top: 0; right: 8px;
    min-width: 18px; height: 18px;
    background: var(--color-primary);
    color: var(--color-text-inverse);
    border-radius: var(--radius-full);
    font-size: 10px; font-weight: 700;
    display: flex; align-items: center; justify-content: center;
}

/* Buttons */
.btn {
    display: inline-flex; align-items: center; justify-content: center;
    gap: var(--space-2); padding: var(--space-3) var(--space-5);
    font-size: 1rem; font-weight: 600;
    border-radius: var(--radius-lg);
    transition: all var(--transition-fast);
    white-space: nowrap;
}
.btn--primary { background: var(--color-primary); color: var(--color-text-inverse); }
.btn--primary:hover { background: var(--color-primary-dark); }
.btn--secondary { background: var(--color-surface); color: var(--color-text); border: 1px solid var(--color-border); }
.btn--secondary:hover { background: var(--color-bg); }
.btn--ghost { background: transparent; color: var(--color-text-secondary); }
.btn--ghost:hover { background: var(--color-bg); color: var(--color-text); }
.btn--danger { background: var(--color-error); color: var(--color-text-inverse); }
.btn--success { background: var(--color-success); color: var(--color-text-inverse); }
.btn--sm { padding: var(--space-2) var(--space-3); font-size: 0.875rem; }
.btn--lg { padding: var(--space-4) var(--space-6); font-size: 1.125rem; }
.btn--block { width: 100%; }
.btn--icon { padding: var(--space-2); border-radius: var(--radius-md); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }

/* Cards */
.card { background: var(--color-surface); border-radius: var(--radius-xl); box-shadow: var(--shadow-sm); overflow: hidden; }
.card--elevated { box-shadow: var(--shadow-md); }
.card__body { padding: var(--space-4); }

/* Tags */
.tag {
    display: inline-flex; align-items: center; gap: var(--space-1);
    padding: var(--space-1) var(--space-2);
    font-size: 0.75rem; font-weight: 500;
    border-radius: var(--radius-full);
    background: var(--color-bg); color: var(--color-text-secondary);
}
.tag--primary { background: var(--color-primary-bg); color: var(--color-primary); }
.tag--secondary { background: #f0fdfa; color: var(--color-secondary); }
.tag--sm { padding: 2px var(--space-2); font-size: 10px; }

/* Exercise Card */
.exercise-card {
    display: flex; gap: var(--space-3); padding: var(--space-3);
    background: var(--color-surface); border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm); cursor: pointer;
    transition: all var(--transition-fast);
}
.exercise-card:active { transform: scale(0.98); }
.exercise-card__thumb {
    width: 80px; height: 80px;
    border-radius: var(--radius-md); overflow: hidden;
    flex-shrink: 0; background: var(--color-bg);
}
.exercise-card__thumb img { width: 100%; height: 100%; object-fit: cover; }
.exercise-card__content { flex: 1; min-width: 0; display: flex; flex-direction: column; }
.exercise-card__title { font-weight: 600; margin-bottom: var(--space-1); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.exercise-card__tags { display: flex; flex-wrap: wrap; gap: var(--space-1); margin-top: auto; }
.exercise-card__action { align-self: center; flex-shrink: 0; }

/* Exercise List */
.exercise-list { display: flex; flex-direction: column; gap: var(--space-3); }

/* Filter */
.filter-group { margin-bottom: var(--space-4); }
.filter-group__title { font-size: 0.875rem; font-weight: 600; color: var(--color-text-secondary); margin-bottom: var(--space-2); text-transform: uppercase; letter-spacing: 0.05em; }
.filter-chips { display: flex; flex-wrap: wrap; gap: var(--space-2); }
.filter-chip {
    padding: var(--space-2) var(--space-3);
    font-size: 0.875rem; font-weight: 500;
    border-radius: var(--radius-full);
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    color: var(--color-text-secondary);
    transition: all var(--transition-fast);
}
.filter-chip:active, .filter-chip.active {
    background: var(--color-primary);
    border-color: var(--color-primary);
    color: var(--color-text-inverse);
}

/* Search Bar */
.search-bar { position: relative; margin-bottom: var(--space-4); }
.search-bar__icon { position: absolute; left: var(--space-4); top: 50%; transform: translateY(-50%); width: 20px; height: 20px; color: var(--color-text-muted); }
.search-bar__input {
    width: 100%; padding: var(--space-3) var(--space-4);
    padding-left: calc(var(--space-4) + 20px + var(--space-2));
    font-size: 1rem; border: 1px solid var(--color-border);
    border-radius: var(--radius-full); background: var(--color-surface);
}
.search-bar__input:focus { outline: none; border-color: var(--color-primary); }

/* Forms */
.form-group { margin-bottom: var(--space-4); }
.form-label { display: block; font-size: 0.875rem; font-weight: 500; color: var(--color-text-secondary); margin-bottom: var(--space-2); }
.form-input {
    width: 100%; padding: var(--space-3) var(--space-4);
    font-size: 1rem; border: 1px solid var(--color-border);
    border-radius: var(--radius-lg); background: var(--color-surface);
    color: var(--color-text); transition: border-color var(--transition-fast);
}
.form-input:focus { outline: none; border-color: var(--color-primary); box-shadow: 0 0 0 3px var(--color-primary-bg); }
.form-input--lg { padding: var(--space-4) var(--space-5); font-size: 1.125rem; text-align: center; letter-spacing: 0.1em; text-transform: uppercase; }
.form-error { font-size: 0.875rem; color: var(--color-error); margin-top: var(--space-2); }

/* Session List */
.session-list { display: flex; flex-direction: column; gap: var(--space-2); }
.session-item {
    display: flex; align-items: center; gap: var(--space-3); padding: var(--space-3);
    background: var(--color-surface); border-radius: var(--radius-lg); box-shadow: var(--shadow-sm);
    transition: all var(--transition-fast);
}
.session-item.dragging { opacity: 0.5; transform: scale(1.02); box-shadow: var(--shadow-lg); }
.session-item__handle { cursor: grab; color: var(--color-text-muted); padding: var(--space-2); }
.session-item__handle:active { cursor: grabbing; }
.session-item__position {
    width: 28px; height: 28px; border-radius: var(--radius-full);
    background: var(--color-primary-bg); color: var(--color-primary);
    font-size: 0.875rem; font-weight: 700;
    display: flex; align-items: center; justify-content: center; flex-shrink: 0;
}
.session-item__thumb { width: 56px; height: 56px; border-radius: var(--radius-md); overflow: hidden; flex-shrink: 0; background: var(--color-bg); }
.session-item__thumb img { width: 100%; height: 100%; object-fit: cover; }
.session-item__content { flex: 1; min-width: 0; }
.session-item__title { font-weight: 500; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.session-item__remove { color: var(--color-text-muted); padding: var(--space-2); }
.session-item__remove:hover { color: var(--color-error); }

/* Workout */
.workout { position: fixed; inset: 0; background: var(--color-bg); z-index: var(--z-modal); display: flex; flex-direction: column; }
.workout__header { display: flex; align-items: center; justify-content: space-between; padding: var(--space-4); background: var(--color-surface); border-bottom: 1px solid var(--color-border); }
.workout__progress { font-size: 0.875rem; font-weight: 600; color: var(--color-text-secondary); }
.workout__content { flex: 1; overflow: hidden; display: flex; flex-direction: column; }
.workout__video { flex: 1; background: #000; display: flex; align-items: center; justify-content: center; }
.workout__video video { width: 100%; height: 100%; object-fit: contain; }
.workout__info { 
    padding: var(--space-4); 
    padding-bottom: calc(var(--space-4) + 80px); 
    background: var(--color-surface); 
    overflow-y: auto;
    flex: 1;
}
.workout__title { font-size: 1.25rem; font-weight: 700; margin-bottom: var(--space-2); }
.workout__description { color: var(--color-text-secondary); font-size: 0.875rem; line-height: 1.625; }
.workout__nav { 
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    display: flex; 
    gap: var(--space-3); 
    padding: var(--space-4); 
    padding-bottom: max(var(--space-4), env(safe-area-inset-bottom));
    background: var(--color-surface); 
    border-top: 1px solid var(--color-border);
    z-index: 10;
}
.workout__nav .btn { flex: 1; }

/* Complete */
.complete { text-align: center; padding: var(--space-8) var(--space-4); }
.complete__icon { width: 80px; height: 80px; margin: 0 auto var(--space-6); color: var(--color-success); }
.complete__title { font-size: 1.5rem; margin-bottom: var(--space-2); }
.complete__subtitle { color: var(--color-text-secondary); margin-bottom: var(--space-8); }
.complete__code-box { background: var(--color-bg); border-radius: var(--radius-xl); padding: var(--space-6); margin-bottom: var(--space-6); }
.complete__code-label { font-size: 0.875rem; color: var(--color-text-secondary); margin-bottom: var(--space-3); }
.complete__code { font-family: 'SF Mono', monospace; font-size: 1.875rem; font-weight: 700; letter-spacing: 0.15em; color: var(--color-primary); margin-bottom: var(--space-4); }
.complete__code-hint { font-size: 0.875rem; color: var(--color-text-muted); }
.complete__actions { display: flex; flex-direction: column; gap: var(--space-3); margin-bottom: var(--space-8); }
.complete__support { margin-top: var(--space-8); padding-top: var(--space-6); border-top: 1px solid var(--color-border); }
.complete__support-link { color: var(--color-primary); font-weight: 500; }

/* Unavailable */
.unavailable { display: flex; flex-direction: column; align-items: center; justify-content: center; height: 100%; text-align: center; padding: var(--space-8); color: var(--color-text-muted); }
.unavailable__icon { width: 64px; height: 64px; margin-bottom: var(--space-4); opacity: 0.5; }

/* Modal */
.modal-backdrop { position: fixed; inset: 0; background: rgba(0,0,0,0.5); z-index: var(--z-modal-backdrop); opacity: 0; visibility: hidden; transition: all var(--transition-normal); }
.modal-backdrop.active { opacity: 1; visibility: visible; }
.modal { position: fixed; bottom: 0; left: 0; right: 0; background: var(--color-surface); border-radius: var(--radius-2xl) var(--radius-2xl) 0 0; z-index: var(--z-modal); transform: translateY(100%); transition: transform var(--transition-normal); max-height: 90vh; overflow-y: auto; }
.modal.active { transform: translateY(0); }
.modal__header { display: flex; align-items: center; justify-content: space-between; padding: var(--space-4); border-bottom: 1px solid var(--color-border); position: sticky; top: 0; background: var(--color-surface); }
.modal__title { font-size: 1.125rem; font-weight: 600; }
.modal__body { padding: var(--space-4); }
.modal__footer { padding: var(--space-4); border-top: 1px solid var(--color-border); display: flex; gap: var(--space-3); }
.modal__footer .btn { flex: 1; }

/* Toast */
.toast-container { position: fixed; bottom: calc(var(--nav-height) + var(--space-4)); left: var(--space-4); right: var(--space-4); z-index: var(--z-toast); display: flex; flex-direction: column; gap: var(--space-2); pointer-events: none; }
.toast { background: var(--color-text); color: var(--color-text-inverse); padding: var(--space-3) var(--space-4); border-radius: var(--radius-lg); font-size: 0.875rem; font-weight: 500; box-shadow: var(--shadow-lg); pointer-events: auto; animation: slideUp 0.3s ease; }
.toast--success { background: var(--color-success); }
.toast--error { background: var(--color-error); }
@keyframes slideUp { from { opacity: 0; transform: translateY(20px); } to { opacity: 1; transform: translateY(0); } }

/* Language Selector */
.lang-selector { position: relative; }
.lang-selector__current { display: flex; align-items: center; gap: var(--space-1); padding: var(--space-2); font-size: 0.875rem; font-weight: 500; color: var(--color-text-secondary); border-radius: var(--radius-md); }
.lang-selector__dropdown { position: absolute; top: 100%; right: 0; min-width: 150px; background: var(--color-surface); border-radius: var(--radius-lg); box-shadow: var(--shadow-lg); overflow: hidden; z-index: var(--z-dropdown); opacity: 0; visibility: hidden; transform: translateY(-10px); transition: all var(--transition-fast); }
.lang-selector__dropdown.active { opacity: 1; visibility: visible; transform: translateY(0); }
.lang-selector__option { display: block; width: 100%; padding: var(--space-3) var(--space-4); text-align: left; font-size: 0.875rem; color: var(--color-text); transition: background var(--transition-fast); }
.lang-selector__option:hover, .lang-selector__option.active { background: var(--color-bg); }
.lang-selector__option.active { font-weight: 600; color: var(--color-primary); }

/* Loading */
.loading { display: flex; align-items: center; justify-content: center; padding: var(--space-8); }
.spinner { width: 40px; height: 40px; border: 3px solid var(--color-border); border-top-color: var(--color-primary); border-radius: 50%; animation: spin 0.8s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }

/* Empty State */
.empty-state { text-align: center; padding: var(--space-12) var(--space-4); }
.empty-state__icon { width: 80px; height: 80px; margin: 0 auto var(--space-4); color: var(--color-text-muted); opacity: 0.5; }
.empty-state__title { font-size: 1.125rem; font-weight: 600; margin-bottom: var(--space-2); }
.empty-state__description { color: var(--color-text-secondary); margin-bottom: var(--space-6); }

/* Page Title */
.page-title { margin-bottom: var(--space-6); }
.page-title__main { font-size: 1.5rem; font-weight: 700; margin-bottom: var(--space-1); }
.page-title__sub { color: var(--color-text-secondary); font-size: 0.875rem; }

/* Exercise Detail */
.exercise-detail { padding-bottom: var(--space-8); }
.exercise-detail__video { aspect-ratio: 16/9; background: #000; border-radius: var(--radius-xl); overflow: hidden; margin-bottom: var(--space-4); }
.exercise-detail__video video { width: 100%; height: 100%; object-fit: contain; }
.exercise-detail__header { margin-bottom: var(--space-4); }
.exercise-detail__title { font-size: 1.5rem; font-weight: 700; margin-bottom: var(--space-3); }
.exercise-detail__tags { display: flex; flex-wrap: wrap; gap: var(--space-2); }
.exercise-detail__section { margin-bottom: var(--space-6); }
.exercise-detail__description { color: var(--color-text-secondary); line-height: 1.625; }
.exercise-detail__action { position: fixed; bottom: calc(var(--nav-height) + var(--space-4)); left: var(--space-4); right: var(--space-4); }

/* Utilities */
.text-sm { font-size: 0.875rem; }
.text-muted { color: var(--color-text-muted); }
.text-center { text-align: center; }
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.gap-2 { gap: var(--space-2); }
.gap-4 { gap: var(--space-4); }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }

/* Desktop */
@media (min-width: 768px) {
    :root { --content-padding: var(--space-6); }
    .bottom-nav { max-width: 500px; left: 50%; transform: translateX(-50%); border-radius: var(--radius-2xl) var(--radius-2xl) 0 0; box-shadow: var(--shadow-lg); }
    .exercise-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: var(--space-4); }
	.exercise-detail__action { max-width: 400px; left: 50%; transform: translateX(-50%); }
	.btn--block, .btn--lg, .btn--ghost{ max-width: 400px; margin-left: auto; margin-right: auto; }
    .modal { max-width: 500px; left: 50%; transform: translateX(-50%) translateY(100%); border-radius: var(--radius-2xl); bottom: var(--space-4); }
    .modal.active { transform: translateX(-50%) translateY(0); }
    .complete__actions { flex-direction: row; }
	.workout__nav {
        max-width: 500px;
        left: 50%;
        right: auto;
        transform: translateX(-50%);
    }
	.workout__video, .workout__video video { max-height: 50vh; }
}
@media (min-width: 1024px) {
    .exercise-list { grid-template-columns: repeat(3, 1fr); }
}