:root {
    --bg: #ffffff;
    --surface: #f9fafb;
    --surface-secondary: #f3f4f6;
    --border: #e5e7eb;
    --border-hover: #d1d5db;
    --text: #111827;
    --text-secondary: #4b5563;
    --text-muted: #9ca3af;
    --accent: #000000;
    --accent-hover: #1f2937;
    --accent-light: #f3f4f6;
    --error: #ef4444;
    --radius: 20px;
    --radius-sm: 16px;
    --radius-xs: 12px;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
    --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.08);
    --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

body {
    background: var(--bg);
    color: var(--text);
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.5;
    padding: 24px 16px 40px;
    -webkit-font-smoothing: antialiased;
}

.app {
    max-width: 560px;
    margin: 0 auto;
    width: 100%;
}

/* ================= HEADER ================= */
header {
    text-align: center;
    margin-bottom: 40px;
    padding-top: 16px;
}

header h1 {
    font-size: 2rem;
    font-weight: 800;
    letter-spacing: -0.04em;
    color: var(--text);
    margin-bottom: 8px;
}

header p {
    color: var(--text-secondary);
    font-size: 1rem;
}

/* ================= STEPS ================= */
.step {
    display: none;
    animation: fadeIn 0.4s ease forwards;
}

.step.visible {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(12px); }
    to { opacity: 1; transform: translateY(0); }
}

.step-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 24px;
    color: var(--text);
    letter-spacing: -0.02em;
}

/* ================= CARDS & GRIDS ================= */
.services-grid, .masters-grid {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.service-card, .master-card {
    position: relative;
    background: #fff;
    border: 2px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 20px 24px;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    flex-direction: column;
    justify-content: center;
    min-height: 80px;
    box-shadow: var(--shadow-sm);
}

/* Выделение выбранной услуги или мастера */
.service-card.selected, .master-card.selected {
    border-color: var(--accent) !important;
    background-color: var(--accent-light) !important;
    box-shadow: var(--shadow-md);
    transform: translateY(-1px);
}

/* Галочка для выбранной услуги */
.service-card .service-checkbox {
    position: absolute;
    right: 20px;
    top: 50%;
    transform: translateY(-50%);
    width: 24px;
    height: 24px;
    border-radius: 50%;
    border: 2px solid var(--border);
    background-color: #fff;
    transition: var(--transition);
}

.service-card .service-checkbox.checked {
    border-color: var(--accent);
    background-color: var(--accent);
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='white' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='20 6 9 17 4 12'%3E%3C/polyline%3E%3C/svg%3E");
    background-size: 14px;
    background-position: center;
    background-repeat: no-repeat;
}

.service-info {
    padding-right: 40px;
}

.service-name, .master-name {
    font-weight: 700;
    font-size: 1.1rem;
    margin-bottom: 6px;
    color: var(--text);
}

.service-details, .master-specialty {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* Специфика карточки мастера */
.master-card {
    flex-direction: column;
    align-items: flex-start;
}

.master-header {
    width: 100%;
    margin-bottom: 16px;
}

.master-rating {
    font-size: 0.85rem;
    color: #fbbf24;
    margin-top: 4px;
}

.master-rating span {
    color: var(--text-muted);
    font-size: 0.75rem;
    margin-left: 6px;
}

.master-slots {
    margin-top: 16px;
    width: 100%;
    border-top: 1px dashed var(--border);
    padding-top: 16px;
}

.master-slots-title {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 12px;
}

.slot-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.slot-btn-small {
    background: #fff;
    border: 2px solid var(--border);
    color: var(--text);
    padding: 8px 16px;
    border-radius: 40px;
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.slot-btn-small:active {
    transform: scale(0.95);
}

/* ================= DATE SELECTOR ================= */
.date-selector {
    margin: 0 -16px 32px;
    padding: 0 16px;
    position: relative;
}

.dates-scroll {
    display: flex;
    gap: 12px;
    overflow-x: auto;
    padding-bottom: 12px;
    scrollbar-width: none;
    -webkit-overflow-scrolling: touch;
    scroll-snap-type: x mandatory;
}

.dates-scroll::-webkit-scrollbar {
    display: none;
}

.date-btn {
    flex: 0 0 auto;
    background: #fff;
    border: 2px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--text);
    padding: 12px 16px;
    cursor: pointer;
    transition: var(--transition);
    min-width: 85px;
    text-align: center;
    display: flex;
    flex-direction: column;
    gap: 4px;
    align-items: center;
    scroll-snap-align: start;
}

.date-btn .day-name {
    font-size: 0.7rem;
    text-transform: uppercase;
    font-weight: 700;
    letter-spacing: 0.05em;
    color: var(--text-muted);
}

.date-btn .day-number {
    font-size: 1rem;
    font-weight: 700;
}

.date-btn.weekend .day-name {
    color: var(--error);
}

.date-btn.active {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    transform: translateY(-2px);
}

.date-btn.active .day-name {
    color: rgba(255, 255, 255, 0.8);
}

.date-selector::after {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 40px;
    height: 100%;
    background: linear-gradient(to left, var(--bg), transparent);
    pointer-events: none;
}

/* ================= TIME SLOTS ================= */
.time-periods-wrapper {
    display: flex;
    flex-direction: column;
    gap: 28px;
}

.time-period-title {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 14px;
    padding-left: 4px;
}

.time-slots-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(85px, 1fr));
    gap: 12px;
}

.slot-btn {
    background: #fff;
    border: 2px solid var(--border);
    color: var(--text);
    padding: 14px 8px;
    border-radius: var(--radius-xs);
    font-weight: 600;
    font-size: 1rem;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
}

.slot-btn:active {
    transform: scale(0.96);
}

.slot-btn.selected {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.no-slots {
    grid-column: 1 / -1;
    color: var(--text-muted);
    font-size: 0.9rem;
    padding: 20px 0;
    text-align: center;
}

/* ================= FORMS & INFO ================= */
.selected-master, .booking-summary {
    background: var(--surface);
    border-radius: var(--radius-sm);
    padding: 20px;
    margin-bottom: 28px;
    font-size: 1rem;
    font-weight: 500;
    border: 1px solid var(--border);
    line-height: 1.6;
}

.selected-master strong, .booking-summary strong {
    color: var(--accent);
}

#clientForm input[type="text"],
#clientForm input[type="tel"],
#clientForm input[type="email"],
#clientForm textarea {
    width: 100%;
    background: #fff;
    border: 2px solid var(--border);
    padding: 16px 18px;
    border-radius: var(--radius-xs);
    margin-bottom: 16px;
    font-family: inherit;
    font-size: 16px;
    color: var(--text);
    transition: var(--transition);
    outline: none;
    -webkit-appearance: none;
}

#clientForm input::placeholder,
#clientForm textarea::placeholder {
    color: var(--text-muted);
}

#clientForm input:focus,
#clientForm textarea:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(0, 0, 0, 0.05);
}

#clientForm textarea {
    resize: vertical;
    min-height: 100px;
}

/* ================= CHECKBOXES ================= */
.consent-checkboxes {
    display: flex;
    flex-direction: column;
    gap: 16px;
    margin: 24px 0;
    width: 100%;
}

.consent-label {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    cursor: pointer;
    user-select: none;
}

.consent-label input[type="checkbox"] {
    flex: 0 0 20px;
    width: 20px;
    height: 20px;
    margin-top: 2px;
    cursor: pointer;
    appearance: none;
    -webkit-appearance: none;
    background-color: #fff;
    border: 2px solid var(--border);
    border-radius: 5px;
    transition: all 0.2s ease;
}

.consent-label input[type="checkbox"]:checked {
    background-color: var(--accent);
    border-color: var(--accent);
}

.consent-label input[type="checkbox"]::before {
    content: "";
    width: 10px;
    height: 10px;
    transform: scale(0);
    transition: 0.2s transform;
    background-color: #fff;
    clip-path: polygon(14% 44%, 0 65%, 50% 100%, 100% 16%, 80% 0%, 43% 62%);
    display: block;
    margin: 3px auto;
}

.consent-label input[type="checkbox"]:checked::before {
    transform: scale(1);
}

.consent-label span {
    flex: 1;
    font-size: 0.85rem;
    line-height: 1.45;
    color: var(--text-secondary);
}

.consent-label.required span::after {
    content: " *";
    color: var(--error);
}

.consent-label a {
    color: var(--text);
    text-decoration: underline;
    font-weight: 500;
}

.consent-label a:hover {
    color: var(--accent);
}

/* ================= BUTTONS ================= */
.btn-primary, .btn-secondary, #submitBtn {
    border: none;
    padding: 16px 24px;
    border-radius: var(--radius-xs);
    font-family: inherit;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    width: 100%;
    transition: var(--transition);
    display: flex;
    justify-content: center;
    align-items: center;
}

.btn-primary, #submitBtn {
    background: var(--accent);
    color: #fff;
    margin-top: 28px;
}

.btn-primary:disabled {
    background: var(--surface-secondary);
    color: var(--text-muted);
    cursor: not-allowed;
    opacity: 0.6;
}

.btn-primary:active:not(:disabled), #submitBtn:active {
    transform: scale(0.98);
}

.btn-secondary {
    background: transparent;
    color: var(--text-secondary);
    margin-top: 12px;
    border: 2px solid transparent;
}

.btn-secondary:active {
    background: var(--surface);
    transform: scale(0.98);
}

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

.loading-overlay {
    position: fixed;
    inset: 0;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 999;
}

.spinner {
    width: 44px;
    height: 44px;
    border: 3px solid var(--surface-secondary);
    border-top-color: var(--accent);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

@keyframes spin { to { transform: rotate(360deg); } }

/* ================= DESKTOP STYLES ================= */
@media (min-width: 640px) {
    body { 
        padding: 40px 24px; 
    }
    
    .date-selector {
        margin: 0 0 32px 0;
        padding: 0;
    }
    
    .date-selector::after { 
        display: none; 
    }
    
    .dates-scroll {
        display: grid;
        grid-template-columns: repeat(7, 1fr);
        gap: 10px;
        overflow-x: visible;
    }
    
    .date-btn {
        min-width: 0;
        padding: 14px 8px;
    }
    
    .date-btn:hover:not(.active) {
        border-color: var(--border-hover);
        background: var(--surface);
        transform: translateY(-1px);
    }
    
    .btn-primary:hover:not(:disabled), #submitBtn:hover {
        background: var(--accent-hover);
        transform: translateY(-2px);
        box-shadow: var(--shadow-md);
    }
    
    .btn-secondary:hover {
        background: var(--surface);
        border-color: var(--border);
    }
    
    .slot-btn:hover:not(.selected) {
        border-color: var(--border-hover);
        background: var(--surface);
        transform: translateY(-2px);
    }
    
    .slot-btn-small:hover {
        border-color: var(--accent);
        color: var(--accent);
        background: var(--accent-light);
    }
    
    .service-card:hover, .master-card:hover {
        border-color: var(--border-hover);
        transform: translateY(-2px);
    }
}

/* ================= АДАПТИВ ДЛЯ МАЛЕНЬКИХ ЭКРАНОВ ================= */
@media (max-width: 480px) {
    body {
        padding: 16px 12px 32px;
    }
    
    .service-card, .master-card {
        padding: 16px 20px;
    }
    
    .service-name, .master-name {
        font-size: 1rem;
    }
    
    .step-title {
        font-size: 1.25rem;
        margin-bottom: 20px;
    }
    
    .time-slots-grid {
        grid-template-columns: repeat(auto-fill, minmax(75px, 1fr));
        gap: 10px;
    }
    
    .slot-btn {
        padding: 12px 6px;
        font-size: 0.9rem;
    }
    
    .date-btn {
        min-width: 70px;
        padding: 10px 12px;
    }
}