/* ===== CSS Variables ===== */
:root {
    --bg-primary: #0a0a0a;
    --bg-secondary: #111111;
    --bg-tertiary: #1a1a1a;
    --text-primary: #ffffff;
    --text-secondary: #a0a0a0;
    --text-muted: #666666;
    --teal-primary: #00d4aa;
    --teal-secondary: #00b894;
    --teal-dark: #008f72;
    --teal-glow: rgba(0, 212, 170, 0.3);
    --red-focus: #ff4757;
    --red-glow: rgba(255, 71, 87, 0.3);
    --border-color: #2a2a2a;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===== Reset & Base ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ===== Container ===== */
.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 2rem;
    min-height: 100vh;
}

/* ===== Header ===== */
.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem 0;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 2rem;
}

.date-display {
    font-size: 1.1rem;
    font-weight: 500;
    color: var(--text-secondary);
    letter-spacing: 0.5px;
}

.date-display strong {
    color: var(--teal-primary);
    font-weight: 600;
}

.settings-btn {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 1.3rem;
    width: 44px;
    height: 44px;
    border-radius: 12px;
    cursor: pointer;
    transition: var(--transition);
}

.settings-btn:hover {
    background: var(--bg-secondary);
    color: var(--teal-primary);
    border-color: var(--teal-primary);
}

/* ===== Mode Toggle ===== */
.mode-toggle {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin-bottom: 2rem;
}

.mode-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    padding: 2rem;
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: 16px;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.mode-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, transparent 0%, rgba(0, 212, 170, 0.05) 100%);
    opacity: 0;
    transition: var(--transition);
}

.mode-btn:hover {
    border-color: var(--teal-primary);
    background: var(--bg-tertiary);
    transform: translateY(-2px);
}

.mode-btn:hover::before {
    opacity: 1;
}

.mode-btn.active {
    border-color: var(--teal-primary);
    background: var(--bg-tertiary);
    box-shadow: 0 0 40px var(--teal-glow), inset 0 0 60px rgba(0, 212, 170, 0.1);
}

.mode-btn.active .mode-icon {
    transform: scale(1.1);
    filter: drop-shadow(0 0 20px var(--teal-glow));
}

.mode-icon {
    font-size: 2.5rem;
    transition: var(--transition);
}

.mode-label {
    font-size: 0.85rem;
    font-weight: 600;
    letter-spacing: 1.5px;
    color: var(--text-secondary);
}

.mode-btn.active .mode-label {
    color: var(--teal-primary);
}

/* ===== Current Mode Display ===== */
.current-mode {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    padding: 1rem;
    background: var(--bg-secondary);
    border-radius: 12px;
    margin-bottom: 2rem;
    border: 1px solid var(--border-color);
}

.mode-indicator {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--teal-primary);
    box-shadow: 0 0 20px var(--teal-glow);
    animation: pulse 2s ease-in-out infinite;
}

.mode-text {
    font-size: 0.9rem;
    font-weight: 600;
    letter-spacing: 1px;
    color: var(--text-secondary);
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

/* ===== Sections ===== */
.section-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    letter-spacing: -0.5px;
}

.section-subtitle {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-bottom: 1.5rem;
}

/* ===== Plan Section ===== */
.plan-section {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 2rem;
    margin-bottom: 2rem;
}

.execution-selection {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem;
    margin-bottom: 2rem;
}

.execution-selection h3 {
    font-size: 1rem;
    font-weight: 700;
    color: var(--teal-primary);
    margin-bottom: 0.5rem;
    letter-spacing: 0.5px;
}

.selection-goal {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.rule-of-thumb {
    background: linear-gradient(135deg, rgba(255, 71, 87, 0.15), rgba(255, 71, 87, 0.05));
    border: 2px solid var(--red-focus);
    border-radius: 10px;
    padding: 1.25rem;
    margin-bottom: 1.5rem;
    text-align: center;
}

.rule-of-thumb p {
    color: var(--text-primary);
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.rule-of-thumb p:last-child {
    margin-bottom: 0;
}

.rule-of-thumb .rule-note {
    color: var(--text-secondary);
    font-size: 0.85rem;
    font-weight: 400;
}

.selection-order {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.selection-item {
    display: flex;
    gap: 1rem;
    padding: 1rem;
    background: var(--bg-secondary);
    border-radius: 10px;
    border: 1px solid var(--border-color);
    transition: var(--transition);
}

.selection-item:hover {
    border-color: var(--teal-dark);
}

.selection-question {
    background: linear-gradient(135deg, rgba(0, 212, 170, 0.15), rgba(0, 212, 170, 0.05));
    border: 1px dashed var(--teal-primary);
    border-radius: 10px;
    padding: 1rem;
    text-align: center;
    margin: 0.5rem 0;
}

.selection-question .question-text {
    color: var(--teal-primary);
    font-size: 0.95rem;
    font-weight: 700;
    margin: 0;
}

.selection-number {
    font-size: 1.5rem;
    flex-shrink: 0;
}

.selection-content h4 {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.selection-content p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.6;
    margin-bottom: 0.25rem;
}

.selection-note {
    color: var(--text-muted);
    font-size: 0.85rem;
    font-style: italic;
    margin-top: 0.5rem !important;
}

.selection-warning {
    background: linear-gradient(135deg, rgba(0, 212, 170, 0.1), rgba(0, 212, 170, 0.05));
    border: 1px solid var(--teal-dark);
    border-radius: 10px;
    padding: 1rem;
    text-align: center;
}

.selection-warning p {
    color: var(--teal-primary);
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.selection-warning p:last-child {
    margin-bottom: 0;
}

.plan-complete {
    text-align: center;
    margin: 2rem 0;
    padding: 1.5rem;
    background: linear-gradient(135deg, rgba(0, 212, 170, 0.1), rgba(0, 212, 170, 0.05));
    border: 2px solid var(--teal-primary);
    border-radius: 16px;
}

.plan-complete-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.75rem;
    padding: 1rem 2rem;
    background: transparent;
    border: 2px solid var(--teal-primary);
    border-radius: 12px;
    color: var(--teal-primary);
    font-size: 1.1rem;
    font-weight: 700;
    cursor: pointer;
    transition: var(--transition);
}

.plan-complete-btn:hover {
    background: var(--teal-glow);
    transform: translateY(-3px);
    box-shadow: 0 10px 40px var(--teal-glow);
}

.plan-complete-btn .checkmark {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    background: var(--bg-primary);
    border-radius: 50%;
    font-size: 1.2rem;
    color: var(--teal-primary);
}

.plan-complete-note {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-top: 1rem;
    font-style: italic;
}

.start-execute-btn {
    width: 100%;
    padding: 1.25rem;
    background: linear-gradient(135deg, var(--teal-primary), var(--teal-secondary));
    border: none;
    border-radius: 12px;
    color: var(--bg-primary);
    font-size: 1rem;
    font-weight: 700;
    letter-spacing: 1px;
    cursor: pointer;
    transition: var(--transition);
    text-transform: uppercase;
}

.start-execute-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px var(--teal-glow);
}

.start-execute-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

/* ===== Execute Section ===== */
.execute-section {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 2rem;
    margin-bottom: 2rem;
}

.execute-container {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.execute-content {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    padding: 1rem 0;
}

.execute-rule {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem;
}

.execute-rule p {
    color: var(--text-secondary);
    font-size: 1rem;
    margin-bottom: 0.75rem;
    line-height: 1.8;
}

.execute-rule p:last-child {
    margin-bottom: 0;
}

.execute-rule strong {
    color: var(--teal-primary);
}

.execute-warning {
    background: linear-gradient(135deg, rgba(0, 212, 170, 0.1), rgba(0, 212, 170, 0.05));
    border: 1px solid var(--teal-dark);
    border-radius: 12px;
    padding: 1.5rem;
}

.execute-warning p {
    color: var(--teal-primary);
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.execute-warning p:last-child {
    margin-bottom: 0;
}

.execute-during {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem;
}

.execute-during h3 {
    font-size: 1rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 1rem;
    letter-spacing: 0.5px;
}

.execute-during p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 0.75rem;
    line-height: 1.7;
}

.execute-during ul {
    margin: 1rem 0;
    padding-left: 1.5rem;
}

.execute-during li {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 0.5rem;
    line-height: 1.6;
}

.execute-during li ul {
    margin-top: 0.5rem;
    padding-left: 1rem;
}

.execute-during .highlight {
    color: var(--teal-primary);
    font-weight: 600;
    margin-top: 1rem;
}

.execute-energy {
    background: linear-gradient(135deg, var(--teal-glow), rgba(0, 212, 170, 0.15));
    border: 2px solid var(--teal-primary);
    border-radius: 12px;
    padding: 1.5rem;
    text-align: center;
    box-shadow: 0 0 30px var(--teal-glow);
}

.execute-energy .energy-text {
    color: var(--teal-primary);
    font-size: 1.25rem;
    font-weight: 800;
    margin-bottom: 0.75rem;
    letter-spacing: 1px;
    text-transform: uppercase;
}

.execute-energy .energy-desc {
    color: var(--text-secondary);
    font-size: 1rem;
    line-height: 1.7;
}

.execute-energy .energy-desc strong {
    color: var(--teal-primary);
    font-weight: 700;
}

/* ===== Principles Section ===== */
.principles-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.principle-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem;
    transition: var(--transition);
}

.principle-card:hover {
    border-color: var(--teal-primary);
    transform: translateY(-2px);
}

.principle-card h3 {
    font-size: 0.9rem;
    font-weight: 700;
    letter-spacing: 1px;
    color: var(--teal-primary);
    margin-bottom: 0.75rem;
    text-transform: uppercase;
}

.principle-card p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ===== Modal ===== */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(10px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    padding: 1rem;
}

.modal-content {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    width: 100%;
    max-width: 450px;
    padding: 2rem;
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
}

.modal-header h2 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
}

.close-btn {
    background: transparent;
    border: none;
    color: var(--text-muted);
    font-size: 1.5rem;
    cursor: pointer;
    padding: 0.5rem;
    transition: var(--transition);
}

.close-btn:hover {
    color: var(--text-primary);
}

.modal-body {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
    margin-bottom: 1.5rem;
}

.setting-item {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.setting-item label {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
    letter-spacing: 0.5px;
    text-transform: uppercase;
}

.setting-item select,
.setting-item input[type="time"] {
    padding: 0.875rem 1rem;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    color: var(--text-primary);
    font-size: 1rem;
    font-family: inherit;
    cursor: pointer;
    transition: var(--transition);
}

.setting-item select:focus,
.setting-item input[type="time"]:focus {
    outline: none;
    border-color: var(--teal-primary);
    box-shadow: 0 0 0 3px var(--teal-glow);
}

.save-settings-btn {
    width: 100%;
    padding: 1rem;
    background: var(--teal-primary);
    border: none;
    border-radius: 12px;
    color: var(--bg-primary);
    font-size: 1rem;
    font-weight: 700;
    cursor: pointer;
    transition: var(--transition);
}

.save-settings-btn:hover {
    background: var(--teal-secondary);
    transform: translateY(-2px);
}

.reset-day-btn {
    width: 100%;
    padding: 0.875rem;
    background: transparent;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    color: var(--text-secondary);
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    margin-top: 0.75rem;
}

.reset-day-btn:hover {
    border-color: var(--teal-primary);
    color: var(--teal-primary);
    background: var(--teal-glow);
}

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

/* ===== Responsive ===== */
@media (max-width: 600px) {
    .container {
        padding: 1rem;
    }

    .mode-toggle {
        grid-template-columns: 1fr;
    }

    .mode-btn {
        padding: 1.25rem;
        flex-direction: row;
        justify-content: flex-start;
        gap: 1rem;
    }

    .mode-icon {
        font-size: 1.5rem;
    }

    .principles-section {
        grid-template-columns: 1fr;
    }

    .plan-task {
        padding: 0.75rem;
    }

    .plan-task label {
        font-size: 0.9rem;
    }
}

/* ===== Scrollbar ===== */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}