:root {
    --color-blue: #0090ff;
    --color-green: #32e697;
    --color-red: #e63258;
    --color-grey-dark: #4b4b4b;
    --color-grey-light: #a4a4a4;
    --color-grey: #a1a1a1;
    --color-white: #ffffff;
    --color-white-muted: #f5f5ee;
    --color-black: #111111;
    --color-bg: #f5f7fa;
    --color-border: #e4e8ed;

    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 22px;

    --shadow-card: 0 10px 32px rgba(17, 17, 17, 0.08);
    --max-content: 1180px;
}

* { box-sizing: border-box; }

/* Ensure the native HTML hidden attribute always wins over component display rules. */
[hidden] { display: none !important; }

html { min-height: 100%; }

body {
    margin: 0;
    min-height: 100vh;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    color: var(--color-grey-dark);
    background: var(--color-bg);
    -webkit-font-smoothing: antialiased;
}

button, input { font: inherit; }

button { touch-action: manipulation; }

h1, h2, p { margin-top: 0; }

.brand-mark {
    display: grid;
    place-items: center;
    width: 58px;
    height: 58px;
    border-radius: 18px;
    color: var(--color-white);
    background: var(--color-blue);
    font-weight: 800;
    letter-spacing: -0.04em;
}

.eyebrow {
    margin-bottom: 6px;
    color: var(--color-blue);
    font-size: 0.78rem;
    font-weight: 800;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

.button {
    min-height: 48px;
    padding: 0 20px;
    border: 0;
    border-radius: 12px;
    font-weight: 700;
    cursor: pointer;
}

.button-primary {
    color: var(--color-white);
    background: var(--color-blue);
}

.button-primary:hover { filter: brightness(0.96); }

.button-secondary {
    color: var(--color-grey-dark);
    background: var(--color-white);
    border: 1px solid var(--color-border);
}

.alert {
    padding: 13px 14px;
    border-radius: 10px;
    font-size: 0.94rem;
}

.alert-error {
    color: #8c1730;
    background: #fff0f3;
    border: 1px solid #ffd4dd;
}

.student-placeholder-page {
    display: grid;
    place-items: center;
    padding: 24px;
}

.placeholder-card {
    width: min(560px, 100%);
    padding: 42px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    background: var(--color-white);
    box-shadow: var(--shadow-card);
}

.placeholder-card .brand-mark { margin-bottom: 24px; }