/* Custom properties for easy theme management */
:root {
    --bg-color: #121214;
    --card-bg: #1a1a1e;
    --text-color: #e1e1e6;
    --text-muted: #8d8d99;
    --primary-color: #00b37e;
    --primary-hover: #00875f;
    --border-color: #29292e;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    padding: 1rem;
    line-height: 1.5;
}

header {
    text-align: center;
    margin-bottom: 2rem;
    padding: 1rem 0;
}

.container {
    max-width: 500px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1.5rem;
}

h2 {
    margin-bottom: 1rem;
    font-size: 1.25rem;
}

.subtitle {
    color: var(--text-muted);
    font-size: 0.875rem;
    margin-top: -0.5rem;
    margin-bottom: 1.5rem;
}

.routine-selector {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

/* Form & Input Layouts */
.exercise-block {
    margin-bottom: 2rem;
}

.exercise-block h3 {
    font-size: 1.1rem;
    margin-bottom: 0.75rem;
    border-left: 4px solid var(--primary-color);
    padding-left: 0.5rem;
}

.set-row {
    display: grid;
    grid-template-columns: 0.8fr 2fr 2fr 1fr;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}

.header-row {
    color: var(--text-muted);
    font-size: 0.8rem;
    text-transform: uppercase;
    font-weight: bold;
}

.set-number {
    text-align: center;
    font-weight: bold;
    color: var(--text-muted);
}

/* Interactive Elements (Large tap targets for mobile) */
.input-field {
    background-color: var(--bg-color);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    padding: 0.75rem;
    border-radius: 6px;
    font-size: 1rem;
    text-align: center;
    width: 100%;
}

.input-field:focus {
    outline: none;
    border-color: var(--primary-color);
}

.btn {
    padding: 0.85rem 1rem;
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    font-weight: bold;
    cursor: pointer;
    transition: background 0.2s;
}

.btn-primary {
    background-color: var(--primary-color);
    color: #ffffff;
}

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

.btn-icon {
    background: none;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 0.75rem;
    font-size: 1.1rem;
    cursor: pointer;
    transition: background 0.2s;
}

.btn-icon:hover {
    background-color: var(--border-color);
}

.hidden {
    display: none !important;
}